I. Technical Field
The present invention relates generally to systems and methods for profiling a surface of a sheet product such as a sheet of metal or a metallic alloy.
II. Background of the Related Art
Thin gauge sheet product having tight tolerance (such as, for example, ±0.05 mm) can be manufactured by grinding and polishing the sheet product using a belt-grinding machine. The belt-grinding machine generally includes an abrasive grinding head and a vacuum bed which holds the sheet product flat in position and acts as a datum face to a grinding head. The grinding head itself is typically comprised of a fixed cylinder, around which a grinding belt passes. The vacuum bed, alternatively known as a vacuum chuck, generally has an o-ring groove machined into it such that a vacuum may be applied to hold the sheet product in position on the vacuum bed during grinding.
A conventional process to grind and polish flat thin gauge sheet product includes placing the sheet on the vacuum bed, holding the sheet product flat in position by applying a vacuum followed by passing the vacuum bed under a fixed grinding head numerous times. After each pass, the bed is raised to decrease the gap between the vacuum bed and the grinding head, thus grinding off and thinning the sheet product uniformly across the entire width of the sheet product.
Alternatively, the process to grind and polish tapered thin gauge sheet product can include passing the bed under the grinding head while gradually raising or lowering the bed between two set positions during each pass to gradually change the thickness of the sheet product between the set positions. This technique creates a tapered change in thickness which is uniform across the entire width of the sheet product.
In either of the above cases, the resultant sheet product is of substantially uniform thickness across the full width (i.e., the direction perpendicular to the grinding direction) of the sheet product, with a given surface roughness which itself depends on the grade of abrasive belt utilized and the number of passes performed.
A sheet product with uniform thickness across the full width of the sheet can, in some instances, have an impact on its performance. For example, where increased rigidity or additional material is required in certain regions, an as-formed sheet product must have the additional thickness across its full width. This additional material increases the final component weight and can potentially hinder performance. Both of these results can create additional costs which is undesirable to users of sheet product.
Accordingly, there exists a need in the art for a cost effective technique for producing a sheet product of controlled, variable thickness, which is both sufficiently controllable and repeatable to be utilized as a commercial manufacturing process.